This invention relates to a pet food supplement and process for enhancing immune response and improving the overall health of companion animals such as cats and dogs, and more particularly to a pet food supplement and process which includes beneficial amounts of .beta.-carotene in the animal's diet.
Carotenoids are naturally-occurring plant pigments which are absorbed in varying degrees by different species. Common carotenoids include .beta.-carotene, lycopene, lutein, zeaxanthin, and astaxanthin. These carotenoids (the most extensively studied being .beta.-carotene) are known to play an important role in modulating the immune system and enhancing the health of these species. .beta.-carotene is known to be a precursor to vitamin A and converted to that vitamin by enzymes in the bodies of certain animals including humans and dogs. However, cats do not possess this enzyme and cannot convert .beta.-carotene into vitamin A.
.beta.-carotene is also known to have potent antioxidant activity and serves to protect cell membranes and organelles from oxidative damage in certain species. However, in order to be effective, .beta.-carotene must be present at critical sites in the cell such as the mitochondria, nuclei, and plasma membrane.
Disease prevention is important both in humans as well as companion animals. A healthy immune system plays an important role both in preventing and fighting disease. Some studies have reported only low to undetectable amounts of .beta.-carotene in the circulating blood and organs of dogs. Further, because of the known inability of cats to convert .beta.-carotene to vitamin A, their diets have not included .beta.-carotene supplements. Accordingly, there remains a need in the art for promoting a healthy immune system in companion animals such as dogs and cats.